Pipe bender with bend indicator means on pivotal reaction blocks



1959 R. J. TRAUPMANN 2,867,261

PIPE BENDER WITH BEND INDICATOR MEANS ON PIVOTAL REACTION BLOCKS 2 Sheets-Sheet 1 Filed Feb. 23, 1955 INVENTOR.

ATTORNEYS.

Jan. 6, 1959 R. J. TRAUPMANN PIPE BENDER WITH BEND INDICATOR MEANS Filed Feb. 25, 1955 ON 'PIVOTAL REACTION BLOCKS 2 Sheets-Sheet 2 United States Patent PIPE BENDER BEND INDICATOR MEANS ON PIVOTAL REACTION BLOCKS Raymond J. Traupmann, Wauwatosa, Wis., assignor to Blackhawk Mfg. Co., West Allis, Wis., a corporation of Wisconsin Application February 23, 1955, Serial No. 490,035

4 Claims. (Cl. 153-38) This invention relates generally to improvements in the art of bending elongated rods or tubes to selected shapes, and relates more specifically to various improvements in the construction and operation of relatively portable assemblages for effecting bending of pipes and bars of diverse cross-section.

The primary object of the present invention is to provide an improved pipe or rod bender which besides being simple and dlirable in construction, is highly efficient in operation and flexible in its adaptations.

Prior to my invention, it has been proposed to provide a pipe bending assemblage consisting of a pair of spaced and permanently united rigid approximately triangular plates adapted for attachment 'at the triangle apex to an end of a hydraulic ram cylinder and having two series of alined holes therein extending away from this cylinder end, and an arcuate shoe attachable to the ram plunger for movement thereby intermediate the plates and between a pair of pipe engaging blocks pivotally mounted in selected alined holes of the two series. While this prior pipe bender was fairly satisfactory for producing approximate bends in pipes and rods, it could not be relied upon to create several such bends with sufficlent precision because successive bends applied to similar pipes or rods in like manner would not be identical. Then too, it was relatively difficult because of the permanent union be tween the two side plates of the unit to apply bending shoes of different curvature and reaction blocks of different shapes and sizes; so that the previous bending units not only lacked precision of functioning but also entailed considerable loss of time when changing over from one class of service to another. 1

It is therefore an important object of this invention to provide an improved pipe or rod bending assemblage which is operable with utmost precision, and is also readily convertible from one type of use to another.

Another important object of the invention is to provide an improved compact and portable, but powerful pipe bender which is capable of effectively producing identical successive bends of any desired curvature and magnitude in pipes or rods of various cross-sectional sizes and shapes.

Still another important object of my invention is to provide a sturdy and readily manipulable pipe bending unit having an indicator for facilitating the production of accurately formed bends in tubes of various wall thicknesses without undesirably distorting the crosssections thereof.

An additional important object of the invention is to provide an improved pipe or rod bending assembly which is conveniently applicable to and cooperable with hydraulic rams of various types, and which may be manufactured and sold for diverse uses at moderate cost.

These and other more specific objects and advantages of the invention will be apparent from the following detailed description.

A clear conception of the features constituting the present improvement and of the construction and operaaccompanying and forming a part of this specification in which like reference characters designate the same or similar parts in the various views.

Fig. l is an exploded perspective view of one of the improved portable pipe benders showing both a hydraulic pump and ram for effecting operation thereof, together with a number of bending shoes of various sizes which may be interchangeably applied to the ram plunger, and also illustrating the side plates, the reaction blocks and the indicator completely dismantled;

Fig. 2 is another partially dismantled perspective view of the same pipe bender, but showing the unit assembled except for the removal of the detachable side plate;

Fig. 3 is still another perspective view of the pipe bending device completely assembled and in action while producing a relatively short bend in a pipe or tube of relatively small diameter;

Fig. 4 is a similar perspective view of the assembled unit illustrated in Fig. 3, but showing the mechanism in action while removing a bend from a previously bent pipe or tube of relatively small diameter; and

Fig. 5 is still another perspective view of the assembled pipe bender, also depicting the device in action but while producing a longer bend in a pipe of larger diameter and with the indicator applied in a different manner, than in Fig. 2.

While the invention has been illustrated herein as being advantageously applicable to a hydraulically actuated portable pipe or rod bending unit to produce a compact and conveniently movable and manipulable assemblage, it is not my intention to unnecessarily restrict the use of the improved features by virtue of this limited embodiment; and it is also contemplated that specific de scriptive terms employed herein be given the broadest possible interpretation consistent with the disclosure.

Referring to the drawing, the improved portable pipe bender illustrated therein comprises in general, a ram having a plunger 8 movable within a guiding cylinder 9; a rigid side plate 10 having its mid-portion fixedly attached to the open end of the cylinder 9 and being provided with at least two series of holes 11, 12 diverging away from the cylinder end; another rigid side plate 13 having its mid-portion detachably attachable to the open cylinder end and being provided with at least two similar series of holes 14, 15 diverging away from the cylinder 9 and which are alineable with the corresponding holes 11, 12 respectively of the plate 10; several arcuate pipe engaging shoes 16, 17, 18, 19, 20, 21, of different curvature interchangeably attachable to the outer end of the ram plunger 8 and being movable by the latter intermediate of the plates 10, 13 mid-way between the two sets of diverging holes 11, 14 and 12, 15; a pipe engaging block 22 pivotally cooperable with selected alined holes 11, 14 and 12, 15 on each of the opposite sides of the plunger 8 and of the shoe associated therewith; and an angle bend indicator 23 attachable to one of the blocks 22, either between or beyond the edges of the plates 10, 13. a

The ram assemblage may be of any suitable type having an elongated plunger longitudinally movable along a guiding member, and an hydraulic ram of a well known type has been embodied in the portable unit shown herein. The end of the ram cylinder 9 remote from the side plates 10, 13, may be connected by a coupling 25 and a flexible hose 26, with a suitable hydraulic pump 27 having an actuating lever 28 and a liquid supply reservoir 29, as shown in Fig. 1; and the fixed side plate 10 may be firmly clamped to the opencylinder end by means of a bracket 30 permanently attached to the apex portion of the triangular plate 10. The side of this bracket 30 remote from the plate is provided with a central screw threaded projection 31 and with two protruding parallel pins 32 disposed beyond the opposite sides of this projection; and the outwardly projecting end of the plunger 8 is provided with an annular groove 33 as illustrated in Figs. 1 and 2. The portion of the plunger 8 which slides along the interior of the guide cylinder 9, is preferably provided with a series of graduations 34 as shown in Figs. 3 and 5, for indicating the exact distance which this plunger travels outwardly from its retracted position.

The two approximately triangular side plates 10, 13 may be formed of heavy sheet-metal and are provided with circular and elongated central openings 36 through which the graduations 34 of the plunger 8 are visible as the latter moves outwardly. The removable side plate 13 is also provided near its apex with openings 37 adapted to coact with the protruding pins 32, and has thereon an internally threaded clamp 38 which is cooperable with the screw threaded projection 31 to firmly but detachably secure this plate 13 to "the bracket 30. The series of holes 11, 14 and 12, diverge away from the apex portions of the triangular plates 10, 13 in straight lines, and the two series of holes 14, 15 formed in the detachable plate 13 are preferably provided with interbending operation, and to also permit the reaction blocks 22 to be properly located so as to effectively cooperate secting straight center lines 39 and with indicia 40 4 representing the diameters of tubes or pipes with which the several shoes 16, 17, 18, 19, 20, 21 and the pivot blocks 22 are adapted to cooperate when the latter are associated with certain of the holes. Each of the plates 10, 13 is also provided with two series of other holes 41, 42 and 43, 44 respectively, also connected by straight center lines 39 and of which the corresponding holes in the two side plates are also alined when the device is assembled, and these additional series of holes are also adapted to pivotally receive the reaction blocks 22.

Each of the bending shoes 16, 17, 18, 19, 20, 21 has a recess 46 therein accurately curved to conform with a segment of a circle having a predetermined radius, and the hubs 47 of all of these shoes are bored to snugly fit 1the grooved end of the plunger 8. A tapered pin 48 is transversely insertable through an opening in .each shoe hub 47 and is adapted to coact with the plunger groove 33 so as to retain the shoe upon the plunger end; and each of the reaction blocks 22 is approximately square and has four side notches 49 of different transverse curvature formed therein and is rotatably supported upon a pivot pin 50 the opposite ends of which are adapted to fit within any of the corresponding alined holes formed in the two side plates 10, 13. Each of the blocks 22 is also provided at one end with a series of four corner sockets 51 which are formed to receive pairs of positioning pins 52 protruding from the lower face of the indicator 23, as shown in Fig. 1. This angle indicator 23 consists primarily of a segment or fan shaped plate having a series of bend designating lines 53 and identifying circles 54 on its upper face, these lines 53 radiating from an opening 55 adapted to receive an annular positioning ridge 56 formed on each block 22 and the circles being exposable either through one of the openings in the plate 13 as in Figs. 3 and 4, or outwardly beyond the plate 13 as in Fig. 5, during normal use of the assemblage, as will be later explained.

When the various parts of the improved pipe bender have been properly constructed as above described, they may be readily assembled and utilized to bend tubes or pipes 58, 59 of various diameters from one-half inch to two inches, in the following manner. The side plate 10 may be permanently and rigidly attached to the open end of the ram cylinder 9 with the aid of the bracket 30, while the detachable side plate 13 can be readily removed by merely manipulating the clamp 38 coacting with the threaded projector 31 in order to permit application of a bending shoe 16, 17, 18, 19, 20 or 21 of the required size and curvature to perform the desired with the selected shoe. Assuming the shoe 19 to be of such proper curvature and size, as depicted in Fig. 2, this shoe may be conveniently attached to the outer end of the ram plunger 8 by merely removing the pin 48 from its hub 47 and by thereafter applying the hub bore to the plunger end and by finally inserting the pin 48 through the plunger groove 33 of the plunger.

With the plate 13 still removed, the pivot pins 50 of the blocks 22 may also be applied to the proper holes 11, 12 in the fixed plate 10 and the indicator 23 may be mounted upon one of these reaction blocks 22 after the two blocks have been positioned to present the side notches 49 best suited to coact with the pipe 58 which is to be bent. The side plate 13 may thereafter be applied to the pivot pins 50 and to the positioning pins 32 and locked in position with the aid of the clamp 38 whereupon the shoe 19 will be prevented from rotating about the plunger axis and the retainer pin 48 will also be held in place by the rigid plates 10, 13. The assembled unit is then ready for normal use in producing bends in pipes 58 of external diameter corresponding to the designating numeral 40 nearest to the pivot pins 50 and which correspond in angularity to the reading on the indicator 23 and upon the calibrations 34 of the plunger 8. By properly manipulating the hydraulic pump 27 with the aid of the handle 28 and the pump by-pass valve, the ram plunger 8 may be forced outwardly or retracted at the will of an operator in a well known manner.

Referring specifically to Fig. 3, here a shoe 18 has been caused to cooperate with the indicator 23 and with the reaction blocks 22 to produce a bend of in a one inch tube or pipe 58, which was initially inserted lengthwise between the retracted shoe 18 and the blocks 22. The ram plunger 8 has subsequently been forced outwardly a definite distance as indicated by the calibrations 34 thereon to an extent whereby the arcuate recess 46 of the shoe 18 has produced the desired bend and has also caused the straight portions of the pipe 58 on the opposite sides of the bend and which are tangent to the latter, to swing the reaction blocks 22 about their pivot pins 50 so as to bring the 45 circle 54 of the indicator 23 in alinement with the hole of the series 14 which bears the marking /2". With the several parts of the unit thus positioned, the desired bending. operation will have been completed, and by retracting the plunger 8 so as to release the bending force and by thereafter releasing the clamp 38, the side plate 13 may be easily removed so as to permit free withdrawal of the bent pipe 58.

Referring more particularly to Fig. 4, in this view the previously formed bend in the one inch pipe 58 is about to be either partially or entirely removed, and the use of the indicator 23 is unnecessary. The plunger 8 and the shoe 18 have been retracted as far as possible, and when the side plate 13 was removed as in Fig. 2, the pivot pins 50 of the blocks 22 were applied to alined holes in the outer series 41, 43 and 42, 44 while the pipe 58 with the bend reversed was inserted between these blocks 22 and the shoe 18. With the unit assembled and cooperating with a bent pipe 58 as in Fig. 4,

the hydraulic pump 27 may be operated to force the plunger 8 and the shoe 18 outwardly thereby causing the latter to diminish the bend in the pipe 58 more or less as desired, and the modified pipe may again be easily removed by merely retracting the plunger and shoe and by thereafter releasing the clamp 38 and removing the side plate 13.

Referring especially to Fig. 5, here a shoe 21 of maximum curvature has been caused to cooperate with the indicator 23 and with the reaction blocks 22 while spread apart to the maximum 'extent, to produce a 90 bend in a two inch diameter pipe 59 which was initially inserted between the retracted plunger 8 and the reaction blocks.

The plunger 8 has been moved outwardly to bend the pipe, but when bending such larger diameter pipe 59, the indicator 23 may be reversed, as compared to its use in Fig. 3, and the bending operation should then be continued until the line 53 which is marked 90 in its circle 54 is brought into alinement with the adjacent line 39 of the side plate 13. When such alinement of these two lines 53, 39 has been reached, the pipe 59 will have been accurately bent to a 90 angle with a curvature corresponding to that of the shoe recess 46, and the bent pipe 59 may thereafter be removed by retracting the plunger 8 and by subsequently reelasing the clamp 38 and withdrawing the detachable plate 13.

From the disclosures in Figs. 3, 4 and 5, it will be noted that the improved pipe ebnding unit is adapted to produce or to remove bends of various angularity in or from pipes of diverse diameters, with utmost precision and with little effort. The markings and calibrations on the several parts of the assemblage, and the series of shoes16, 17, 18, 19, 20, 21, together with the quickly detachable side plate 13, enable the operator to obtain the desired results with utmost ease and without marring or collapsing the walls of thin or highly finished pipes or tubes, and the improved indicator 23 which may obviously be caused to cooperate with one of the blocks 22 in any suitable manner constitutes an important part of this invention and insures extreme accuracy of performance and flexibility in use of the apparatus. The equipment is also compact and portable so that it may be manipulated in relatively cramped quarters, and by utilizing a hydraulic ram a powerful unit results although any other type of power device having a guided power plunger may be employed instead of an hydraulic ram. The improved assemblage has proven highly satisfactory and successful in actual use, and can be produced at moderate cost for various uses.

It should be understood that it is not desired to limit ,this invention to the exact details of construction and operation of the pipe bender herein specifically shown and described, for various modifications within the scope of the appended claims may occur to persons skilled in the art.

' I claim:

1. A pipe bender comprising, a plunger movable along a guide member, a rigid plate having its mid-portion fixedly attachable to an end of the guide member and being provided with two series of holes diverging away from said member end, another rigid plate having its midportion detachably attachable to said member end and being provided with two similar series of holes also diverging away from said member end and which are axially alineable with corresponding holes in said fixedly attached plate, the centers of the holes in each series being disposed in a common center-line, a-pipe engaging shoe attachable to said plunger and being movable thereby between said plates mid-way between said diverging series of holes, a pipe engaging block pivotally mounted between said plates to swing about the axis of alined holes of said series on each of the opposite sides of said shoe, and an angle bend indicator connected with and being operable by the movement of one of said blocks and having thereon bend designating indicia alineable with said center line of the adjacent hole series whenever the desired degree of pipe bending has been efiected.

2. A pipe, bender comprising, a plunger reciprocable along a cylinder, a rigid plate fixedly attached to an end of said cylinder and being provided with several series of holes diverging away from said cylinder end, another similar plate detachably attached to said cylinder end and being provided with several series of holes of which the corresponding holes are axially alined with those of said fixed plate, the centers of the holes of each series being disposed in a common straight center-line and said plunger having thereon a series of calibrations while said detachable plate has an opening through which said plunger calibrations are visible as the plunger is moved beyond said cylinder end, a pipe engaging block swingable about the axis of selected axially alined holes of said series on each of the opposite sides of said plunger, and an angle bend indicator operably connected with one of said blocks and having thereon bend designating indicia radiating from the block axis and alineable with said center-line of the adjacent hole series to designate the degree of pipe bending effected by said plunger.

3. A pipe bender comprising, a plunger movable along a guide member, at least one rigid plate having its midportion secured to said guide member and being provided with two series of holes extending away from said member, the centers of the holes of each series being disposed in a common center-line, a pipe engaging shoe attachable to said plunger and being movable thereby mid-way between said series of holes, a pipe engaging reaction block pivotally mounted in selected holes of said series on each of the opposite sides of said shoe, and an indicator connected with and being operable by the movement of one of said blocks and having thereon bend designating indicia visibly alineable with said center-line of the adjacent hole series to indicate the extent to which a pipe being acted upon by said shoe and said blocks has been bent.

4. A pipe bender comprising, power means movable along a guide, at least one plate secured to said guide and having therein two series of holes extending away from the guide, the centers of the holes of each series lying in a common center-line, a shoe movable by said power means along a path between said hole series, a reaction block pivotally mountable in selected holes of said series on each of the opposite sides of said path, and a visible indicator connected with and being operable by the movement of one of said blocks and having thereon bend designating indicia alineable with said center-line of the adjacent hole series to indicate the extent to which a pipe being acted upon by said shoe has been bent.

References Cited in the file of this patent UNITED STATES PATENTS 1,610,196 Blaisdell Dec 7, 1926 1,865,025 Lidseen et al June 28, 1932 1,964,550 Abramson et al June 26, 1934 2,382,266 Simonsen Aug. 14, 1945 2,464,459 Newlon Mar. 15, 1949 2,702,578 Hotiman Feb. 22, 1955 FOREIGN PATENTS 641,531 France Apr. 21, 1928 

